Attachments for try-squares.



A. R. BOEHM.

ATTACHMENT FOR TRY SQUARES. APP! LCATION men NOV. 24. 1911.

Patented Nov. 19, 1918.

INVENTOR,

ATTORNEY ARTHUR R. :BoEHM, or HARTFORD, CONNECTICUT.

ATTACHMELTTS FOR TRY-SQUARES.

Specification of Letters Patent.

Patented Nov. 19, 1918.

Application filed November 24, 1917. Serial No. 203,748.

To all whom it may concern:

Be it known that I, ARTHUR R. BonHM, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Attachments for Try-Squares, of which the following is a specification. I

This invention relates to measuring instruments and more particularly to attachments for try squares and bevel squares.

The object of the invention is to provide a simply constructed and efficient attachment for squares designed to effect a rapid and accurate squaring of the ends of circular work and which may be applied to squares ialready in use as well as to those in the process of being manufactured,and is especially designed for use on squares known on the market as Starrett squares.

vAnother object is to provide an attachment of this character which may be either sold separately or in connection with the square with which it is to be used. 7

With the foregoing and other objectsvin view, which will appear as the description proceeds, the invention resides in the combinationand arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

In the accompanying drawings Figure 1 represents an edge view of a straight edge showing a try square connected with and equipped with this improved attachment,

Fig, 2 is a side elevation thereof,

Fig. 3 is a bottom plan view of one member of the attachment,

Fig. 4 is a detail section taken on the line 44 of Fig. 2,

Fig. 5 is a detail perspective view of one end of a try square showing the slots provided therein for the reception of the attachment constituting this invention,

Fig. 6 is a similar view of the attaching end of the attachment, and

Fig. 7 is a detail perspective view of one end of a try square showing slightly difi'erent means for connecting the attachment thereto.

Fig. 8 is a side elevation showing the invention applied.

In the embodiment illustrated, a try square 1 of ordinary construction is shown used in connection with a straight edge or blade 2 graduated along its opposite edges in the usual manner and provided with a longitudinally disposed central groove 3 which is designed to be slidably engaged by the bifurcated end of square 1.

The attachment constituting this invention comprises a flexible steel band 5 adapted to be detachably connected at one end to one end of the square as shown at 6 in Fig. 2. The means for efi'ecting this connection is shown in Figs. 1 to 6 in the form of an under cut groove 7 channeled in one edge of the square 1 with which is designed to be detachably engaged a wedge shaped or clovetailed rib 8 which has .a longitudinally ex tending slot 9 therein for a purpose presently to be described.

Another flexible steel band or arm 10 is hingedly connected with the outer free end of arm 5 as shown at 11 and is provided with a longitudinally extending slot 12 through which a thumb screw 13 passes and is designed to engage a socket 14 in one end of the square 1 as is shown clearly in Fig. 2. By so connecting this arm 10 with the square it will be obvious that it may be adjusted longitudinally so as to position arm 5 inthe desired relation to the square.

It will thus be seen that this attachment may be quickly connected to and removed from the square 1 which must be provided with a threaded aperture in one end to receive the thumb screw 13 and with the dovetailed or undercut groove at its other end to receive the rib 8 on the attachment. Another thumb screw 15 is shown for connecting the square to the straight edge.

The slot 9 shown in the rib 8 of the attachnient is designed to receive one edge of the blade 2 which passes between bifurcations formed in the end of said square as is shown clearly in Fig. 4..

In the form shown in Fig. 7 the band or arm 5 is connected to the square by rivets 8 and when so connected obviously will form a permanent part of the square.

In the use of this attachment, when employed for instance, in connection with the buildin up of a circular door or window frame rom semi-circular or arcuate pieces of Wood, such as that shown in Fig, 8, it is necessary that the ends be squared OK to fit neatly with the least amount of work and trouble. To do this, the attachment is set after first connecting it with square 1 by sliding the rib 8 into slot 7 and properly positioning screw 13, by trying the/square in the middle of one segment S shown in Fig. 8 (see full lines), then marking line L on said segment, and then trying the square from the other position shown in dotted lines. If it be found that the square is true on line L after several trials, the square with the attachment applied will be ready for use on the ends of all the segments of the same diameter as segment S.

In using the square 1 it must be pressed lightly against the convex edge of the segment S so that band 5 will'snugly fit said edge.

The fittin of the wedge shaped rib or block 8 snugl into slot 7 will tend to curve the spring band 5 on the clamping of band 10 by screw 13; Thus, as only a very slight curve is required, the ordinary pressure in holding the square against the segment, should be sulficient to cause band 5 to fit the segment. I

From the foregoing description, taken in connection With the accompanying drawings, the advantages of the construction and of the method of operationwill be readily ap' parent to those skilled in the art to Which the invention appertains and While I have described the principle of operation of the invention together with the device which I now consider to be the best embodiment thereof, I desire to have it understood that the device shown is merely illustrative and that such changes may be made as are Within the scope of the claimed invention.

ably connecting said hinged arm to said square.

2;, An attachment of the class describedcom-prising two flexible steel bands hingedly connected at one end and one disposed laterally relatively to the other, one of said arms having a longitudinally slottedun'dercut rib at its free end on one face, and the other having a longitudinally extending slot for the passage therethrough of a set screw.

3. In a device of the class described, the combination ofa straight edge having a groove extending longitudinally on one facethereof,fla try square'having a bifurcated end for straddling said straight edge and slidably engaged therewith, sa1d square having a groove in the edge thereof arranged at right angles to the bifurcated edge, sa1d groove having undercut side Walls, an arm having an undercut rib for detachable engagement with the undercut groove 'of' said square, another arm hingedly connected to sa1d first mentioned arm, andmeans for ad justably'connecting said hinged arm to the square. 7

In testimony whereof -I affix my signature 1n presence of twowltnesses.

ARTHUR R; BOEI-IM.

Witnesses:

B. F; RonBEN, K. LERER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,-

Washington, no. 

